Friction shock-absorbing mechanism



1. F. OCONNOR.

FRICTION SHOCK ABSORBING MECHANISM.

APPLICATION FILED NOV- 15, l9l9- Patented Apr. 12, 1921.

n Q N T N m m w m QM v l A- iii! Q k 9 ll l lk MN & a v v23 m N fl Q n N S 9 -m M N k g Q B fihwwfi NW? g um cw J Q an m V RN \N 4 M. v W F N\ AN w x\\\ 3 7 Q a fl O & \wm WEE W.

UNITED STATES PATENT OFFICE.

JOHN I. OCONNOR, OF CHICAGO, ILLINOIS, ASSIGNOR TO WILLIAM H. MINER, 0 CRAZY, NEW YORK.

ERICTION SHOGK-AIBSORBING MECHANISM.

Specification of Letters Patent.

Patented Apr. 12, 1921.

Application filed November 15', 1919. Serial No. 338,182.

To all whom via-may concern:

Be it known that'I, JOHN F. OCoNNoR, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new anduseful Im rovement in Friction Shock-Absorbing echanism, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

This invention relates to improvements in friction shock absorbing mechanism.

One object of the invention is to provide a graduated high capacity friction shock absorbing mechanism especially adapted for railway draft gears and wherein' fi obtained certain release. I

Another and more .specific ob] of the invention is to provide a friction mechanism of the characterdescribed wherein'iare employed two sets of friction shoes" 1th cooperatmg spreading devices, one set Qj-igfricat the end of the compressive stroke. And

Fig. 4 is a perspective view of the wedge block employed with my improvements.

In said drawing, 1010 denote channel sha ed center or draft sills of a railway car to the inner faces of which are secured front stops 11. and rear stops 12 of any desirable form and spaced standard distances apart. A portion ,of a draw-bar is indicated at 13, the same being operatively connected to the shock absorbing mechanism proper by means of a oke 14 of usual form. The shock absorbing mechanism proper, hereinafter described, is mounted within the yoke as is also a front follower 15. The various movable parts are supported by any suitable means such as the detachable saddle plate 16. r

'The shockabsorbing mechanism proper,

side friction faces 17-'17.

as shown, comprises, broad1y, a combined friction shell and spring cage casting A, an outer pair of friction shoes B-B, an inner pair of friction shoes C-C, an outer pair of wedges D -D, a central wedge block E, a main spring resistance-F, a retaining bolt G, a spring cap orwasher H,.and anti-friction rollers KK interposed-between the shoes and the various wedges; Y I

The casting A, as shown, is provided at its outer end with a friction shell proper, the same being substantially rectangular in cross section and having interior parallel I At the year end of. said friction faces 17 the shell is provided with inwardly projectingshoulders 1818 to limit the inward movement of the outer friction shoes BB, as hereinafter explained. Bearwardly of the shoulders 18, the shell is, provided with additional inwardly. extended limiting shoulders 1919- for the inner pair of shoes 0, as hereinafter explained. gAtits rear.;:end, the castingA is formed with an integralwall and lateral extensions, as indicated at 20 so as to adapt the rear end ofthe casting to act as a rear follower for the mechanism.

Each of the outer friction shoesB is provided with an. outer flat friction face 21 which cooperates with the corresponding friction shell face 17. On its inner side, each shoe B is also provided with a wedge face 22, the same being inclined rearwardly and toward. the axis of the mechanism.

Shoulders 23 are formed at the inner'ends of the wedge faces 22 to limit the outward movement of theinner friction shoes C with respect to the shoes B, as will b e apparent the wedges D and shoes B being provided alsov with shoulders 28 and 29 to limit the movements of the rollers K with respect to said members.-

The wedge block E, in addition to its outer wedge surfaces 26 which diverge rearwardly, is provided with an inner pair of D and the block E.

rearwardly converged wedge faces 30-30 opposed to the corresponding wedge faces 3l31 on the inner sides of the friction shoes C. The shoes C and block E are provided with shoulders 32 and 33 to retain the rear pair of anti-friction rollers K in proper position.

The wedge block E is centrally perforated to accommodate the bolt G as is also the spring cap or plate H. the ends of said bolt (1: being retained by the block E at one end and by the rear wall of the casting A at its other end, as clearlyappears from Fig. 1.

The spring F, as shown, comprises an.

outer heavy coil 34 and an inner lighter coil 35. said spring bearing at its rear end against the rear wall of the casting A and at its forward end against the cap H, which in turn bears against inwardly extended shoulders of the shoes C so that movement of the latter is yieldingly resisted by the spring F.

The shoes C are made appreciably shorter than the shoes B for a purpose hereinafter described and the shoes B are provided with interior friction surfaces 36 parallel to the surfaces 17 and cooperable with opposed friction surfaces 37 on the outer sides of the shoes C.

The operation of the mechanism is as follows: Assuming an inward movement of the drawbar. the front follower 15' will be forced rearwardly and during the first part of the compressive stroke. the wedges D, block E,

shoes B and shoes C will travel rearwardly substantially as a unit against the action of the springd and until the shoes B conie into engagement with the shoulders 18. During thispa rt of the stroke. it is evident that friction will be generated between the shoes B and friction surfaces 17 of the castihgA, the spreading action being exerted both directly by the wedges D and indirectly through the block E and shoes'C. \Vhen the shoes B have reached their innermost limit, continued movement of the front follower 15 will force the wedges D rearwardly with respect to the shoes B. Due to the arrangement of wedge faces described. the said continued rearward movement of the wedges D will be accompanied by an inward lateral movement, of the wedges D thereby creating friction between the wedges D and the follower 15 and also between the wedges The combined longitudinal and lateral movement of the wedges D will force the block E rearwardly at a higher rate than that of the wedges D so that the block E will cause the shoes C to travel rearwardly and create friction between the opposed friction surfaces of the shoes C and shoes B. The movement of the parts is limited finally by the engagement of the shoes C with the shoulders 19.and this will preferably occur when the outer faces of the wedges'D become flush with the outer B and the block E will similarly be free to move outwardly with respect to the shoes C and thereby release the friction between the sets of shoes and between the outer set of shoes B and friction shell.

In actual practice, where. the permissible stroke of the mechanism is three inches, that is, where there is normally three inches clearance between the follower 15 and the outer end of the casting A, I will preferably so locate the shoulders 18 and 19 as to per- 'mit of a movement of approximately one and one-half inches of the shoes B, the re- .maining movement of the shoes C being approximately three inches with respect to the shoes B. As will be understood,. these -features may be changed to suit different conditions and the relative amount of movement of the shoes C with respect to the shoes B will be dependent upon the. angles employed in the cooperating wedge faces of the shoes and wedges and block. I

ith the construction shown and described, it is evident that I obtain a gradu- 9 ated frictional resistance and high capacity with large areasof wearing friction surfaces. It will be noted, for instance, that no set of cooperating friction surfaces is in actual sliding action during the entire compressive stroke, but, on the contrary, each set of frici tion surfaces is in relative sliding action during approximately only one-half of the stroke, thereby prolonging the life of the parts. It will also be observed that all of the parts are of such design that.'they may be manufactured at comparatively small expense. I

I claimx 1. In a friction shock absorbing mechanism, the combination with a friction shell and a spring resistance; of a set of friction shoes directly cooperable with said shell; a

second set of friction shoes directlv cooperable with said first set of shoes, said sets of shoes having cooperating friction surfaces extending parallel to the axis of the shell, both sets being located at the sameend of the shell; and spreader means directly cooperable with both sets of shoes to force thein outwardly against the shell.

2. In a friction shock absorbing mechanism, the combination with a friction shell and a spring resistance; of an'outer set of friction shoes cooperable with the shell; an inner set of friction shoes slidable relatively to the outer set of shoes 'on the interior thereof and located at the same end of the shell; and spreader means directly cooperable with both sets of friction shoes.

' friction sur 3. In, a friction shock absorbing mecha-- -nism, the combination with a friction shell cooper-able with both sets of shoes to force' them outwardly against the shell, said spreader meansincludin a air of outer wedges and a central wedge b ock.

4. In a friction shock absorbing mechanism, the combination with a friction shell and a spring resistance, of a set of friction shoes directly cooperable with said shell; a second set of friction shoes directl cooperable with the first named set of s oes; spreader means co-acting with said sets of shoes; and means for limiting the movement of the first set of friction shoes relatively to the shell prior to the end of the compressive stroke, the second set of friction shoes being movable during the remainder of the stroke.

5. In a friction shock absorbing mechanism, the combination with a friction shell and a spring resistance; of an outer set of friction shoes having inner wedge faces; a pair of relatively laterally movable wedges vcotiperable with said shoes; a central wedge block cooper-able with said wedges; and another set of friction shoes having wedge faces cooperable with said block.

6. In a friction shock absorbing mechanism, the combination with a friction shell having longitudinally extending interior aces and limiting shoulders at the inner ends of said surfaces; of a spring resistance; an outer set of friction shoes directly cooperable with said friction surfaces and limited in their inward movement with respect to the shell by said shoulders, said shoes having interior wedge faces; an outer pair of wedges cooperable with said friction shoes and relatively movable laterally; a central wedge block cooperable with said wedges; and an inner pair of friction shoes frictionally cooperable with said first named set of friction shoes and having wedge faces cooperable with said block.

7. In a friction shock absorbing mechanism, the combination with a friction shell having longitudinally extending interior friction surfaces and limiting shoulders at the inner ends of said surfaces; of a spring resistance; an outerset of friction shoes directl cooperable with said friction surfaces and imited in their inward movement with respect to theshell by said shoulders, said shoes having interior wedge faces; an outer pair of wedges cooperable with said friction shoes and relatively movable laterally; a central wedge block cooper-able with said wedges; an inner pair of friction shoes frictionally cooperable with'said first named set of friction shoes and having wedge faces cooperable with said block; and anti-friction rollers interposed between the wedge faces of the shoes and the opposed corresponding faces of the wedges and wedge block.

8. In a friction gear; the combination with a friction shell having interior longitudinall extending friction'surfaces, said shell havlng limiting shoulders at the inner ends of said surfaces; of a follower movable relatively to the shell; a pair of wedges disposed on the inner side of said follower and having friction surfaces cooperable with the latter; an outer pair of friction shoes directly slidable upon said friction surfaces of the shell and limited to movement relatively thereto by said. shoulders, said shoes and, wedges having opposed wedge faces;

anti-friction rollers interposed between said wedge faces; an inner pair of friction shoes frictional ly cooperable with the interior faces of said first named friction shoes, said inner shoes having inner wedge faces; a spring resistance interposed between said inner friction shoes and the shell; a central wedge block having outer wedge faces frictionally cooperable with said wedges and provided also with inner wedge faces opposed to the wedge faces of the inner friction shoes; and anti-friction rollers interposed between the oppos'ed wedge faces of said block andinner friction shoes.

In witness that I claim the foregoing I have hereunto subscribed my name this5th day of Nov., 1919.

JOHN F. OOONNOR. 

